PUGWASH – It sounds unusual for a conservation group to tear trees from the forest.

But that is exactly what took place Sunday in Pugwash.

The Nature Conservancy of Canada organized a group of volunteers to take back the forest and fight an aggressive invader.

Glossy Buckthorn, is an invasive species that has started crowding out native species such as pine and maple trees. Transported from Europe, it was first discovered in Nova Scotia 15 years ago as an ornamental garden plant.

Armed with handsaws, loppers and bug spray to fend off clouds of mosquitoes, the Nature Conservancy of Canada removed five-thousand of the shrubs at its Pugwash Nature Reserve.

If left alone, the glossy buckthorn can grow up to 20 feet tall. The leaves come out early in spring and stay until late fall shading out native plants.

Nature Conservancy of Canada stewardship coordinator Doug van Hemessen says the organization is developing a long term strategy on the glossy buckthorn because of its high seed production. The seeds stay in the soil for three years and are easily carried by birds and animals - allowing the glossy buckthorn to establish quickly in other areas.

van Hemessen said crews had to carefully hang the trees upside down and not allow the roots to touch the ground.

The group used a herbicide mix of glysophate and water to paint on the remaining stumps to prevent the roots from growing.

The unwanted plant, which reduces wildlife habitat, has also been spotted in Annapolis and Antigonish areas of Nova Scotia. It has also been recorded in Prince Edward Island, Ontario and Manitoba.

The Nature Conservancy of Canada has worked in the Atlantic provinces since 1971, acquiring 64,000 acres of privately owned wetlands, forests and coastal shorelines for permanent conservation.